Is a person who died owing years of unpaid zakat on his wealth, and who fasted as expiation for oaths instead of feeding or clothing, considered sinful or excused due to ignorance?

If a person dies owing Zakat that they had not paid for years, then Zakat is not waived due to ignorance or the passage of time; it remains a debt upon them. Their heirs must pay the Zakat from their estate before distributing it, as well as any due expiations if they had fasted in lieu of them, despite being able to feed or clothe, because fasting is not sufficient except in the inability to feed or clothe, as stipulated in verse 89 of Surat Al-Ma'idah.